In various plants, a centrifugal compressor for pumping a process gas is used. In a case where a process gas is pumped by a centrifugal compressor, according to a kind of the process gas, components in the gas react and polymeric or coke-shaped solid matters may be generated in a flow path. In addition, an increase in a temperature of a process gas in a compression step may influence the generation of the solid matters.
If the solid matters attached to a flow path or a rotating member of a centrifugal compressor, the attached solid matters adversely affect a flow in the flow path or decrease performance. In addition, if attachment or separation of the solid matters is generated, balance in the rotating member is lost, which generates vibrations.
Accordingly, for example, PTL 1 discloses a configuration in which a spray-type nozzle is installed to remove solid matters attached to and deposited on a flow path of a centrifugal compressor and an atomized cleaning solution is injected into a flow path.